She generated the biggest press scrum of Paris fashion week with her debut Sunday as creative director for Emanuel Ungaro. But by the time she arrived at the post-fashion show fete at the Plaza Athenee, Ms. Lohan had been stung by scathing reviews. A smaller-than-expected pack trailed her when she stormed in. Ms. Lohan’s bodyguard stood at attention in front of the booth where she sat, unlit cigarette in hand, but no one seemed to be threatening her or even particularly interested in her presence. No mobs of fans outside. Many fashion editors skipped the party entirely. Bigger crowds have turned out for free champagne at store openings.

Lindsay Lohan and Estrella Archs — Ungaro’s legitimate new designer — probably didn’t feel like partying. Yet they both managed to turn up – separately. Ms. Archs, who has worked with other big egos in the past like Miuccia Prada and Christian Lacroix, showed up first, in the same black and white bandage dress she wore for her catwalk bow.

Ms. Lohan, crowned Ungaro’s creative director in the media coup of the fashion season, stormed in later — late — in a black version of a runway look, a strapless minidress with crystals. Ms. Lohan sat in a booth in the dark Philippe Starck-designed bar surrounded by her posse, a bottle of Evian and petit-fours on the table in front of her. Ms. Archs sat at the next table over, her back to her design partner, studying print-outs of reviews from the show.

Ungaro’s chief executive (and mastermind of the media coup), Mounir Moufarrige, put on a brave face and greeted guests including jewelry designer Jade Jagger. The house’s owner, Asim Abdullah, was defiant. Either Ms. Lohan’s name reignites Ungaro, or “we go down in a blaze of glory,” said Mr. Abdullah. “Or unglory.”